Governor for steam-engines



(Nd Model.)

J. 8.. MARSHALL. GOVERNOR FOR STEAM mamas No. 878,170. Patented Feb. 21, 1888.

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, rocking motion to the rock-shaft H through lliiviTnn STaTns PATENT @rrice.

JOHN S. MAR-SHALL, OF IM LAY CITY, MICHIGAN.

GOVERNOR FOR STEAM=ENG!NES.

SPECIFICATION forming part of Letters Patent No. 378,170, dated February 21, 1888.

Application filed October 26, 1887. Serial No. 253,467. (X0 model.)

To all whom it may concern.-

Be it known that I, JOHN S. MARSHALL, a citizen of the United States, residing at Imlay 5 City, in the county of Lapeer and State of Michigan, have invented a new and useful Improvement in Governors for Steam-Engines, of which the following is a specification.

My invention relates to an improvement in governors for steanrengines; and it consists in the peculiar construction and combination of devices, that will be more fully set forth hereinafter, and particularly pointed out in the claims.

In the accompanying drawings, Figure l is a side elevation of a steanrengine provided with a governing apparatus embodying my improvements. Fig. 2 is a top plan view of the same. Figs. 3 and i are detailed views.

A represents the steam cylinder, which is provided with a steam-chest, B, having a balance-valve, preferably of the form shown and described in my pending application for Letters Patent of the United States filed this day.

0 represents a driving-shaft,which is provided with the usual crank, D, connected to the cross-head of the piston-rod by means of a pitman, E.

F represents an eccentric which is secured rigidly to the shaft 0.

The balanced valve in the steam-chest is provided with a projecting stem or rod, G.

H represents a rock-shaft which is journaled in a suitable bearing, 1, on the bed of the engine at a suitable distance in front of the steanrcylinder. At the outer end of the rock-shaft is a crank-arm, K, which is connected to a strap, L, on the eccentric by means of a rod, M.

From the foregoing description it will be readily understood that when the engine is in motion the rotation of the shaft 0 will impart the eccentric and the rod M.

Nrepresents an arm which is rigidly secured to the rock-shaft H and projects upward from the same. At the lower end of the arm, and on opposite sides thereof, are formed ears or studs 0, having vertical openings, through which pass the vertical arms of a U- shaped yoke, P. Near the upper ends of the said arms of the said yoke are placed nuts B. S represents a rectangular box which is made I of metal, and hasavertieal rectangular opening, T, as shown. In one end of the said opening T is arranged atransverse roller, U,which is journaled in the sides of the box, as shown. The opposite end of the box, on its under side, is recessed or cut away to receive a plate, V, which is provided with a central vertical longitudinalslotfl f. Attheinncrendoftheplate V, on opposite sides thereof, are formed ears or bearings, in which is journaled a roller, X, that is similar to the roller U, and is arranged in the opposite end of the openingT from that in which the roller U is located. The box S is provided near its end with vertical central openings adapted to receive the upper endsof the arms of the yoke 1?. One of the said arms of the'said yoke passes, also, through the slot \V, as shown in Fi 4, and to the upper ends of the yokearms are screwed clamping-nuts Y. lhe arm N, which projects upward from the rock-shaft H, passes between the rollers U and X and bears against the opposing sides thereof. The yoke P is free to move vertically through the openingsin the ears or studs 0, and thereby raise or lower the box S, for the purpose to be hereinafter described.

Z represents a connecting-rod which has its inner end hinged or pivoted to the outer end of the valve-stein, and has its outer end bifurcated to form arins A, which are arranged on opposite sides of the box S and are pivoted to trunn ions B, that project from opposite sides of the said box at the center thereof.

0 represents a suitable standard which GX tends upward from the bed-plate of the engine, and has at its upper end a swiveled head, D, which is free to rotate therein, and is provided with diverging arms E.

F represents a pair of levers which are ful- CllllllGd in the upperends of thesaid arms,have their outer ends provided with weight-balls G, and have their inner ends connected to links H, which links are attached to the upper end of a vertical depending rod, 1.

K represents a lever which is arranged on the outer side of the bed of the engine, is fulcrunned to a suitable support, L, and is connected near its front end to the lower end of ICC the rod 1, as shown.

M represents a vertical rod which has its upper end pivotally connected to the connectin g'rod Z, near the front end of the latter, and

its lower end pivotally connected to the front end of the lever K. On the rear arm of the said lever K is secured an adjustable weight, N.

The operation of myinvention is as follows: When the engine is in motion, the rocking motion of the rock-shaft H causes the arm N. to

oscillate, and thereby impartreciprocating mo tion to the box S, which is communicated to the balance cut-off valve through the connecting-rod Z and the valve stem or rod G. The weight N serves to counter-poise the weightballs G of the governor. In the event that the engine should commence running too fast, the weight-balls G will rise by centrifugal force and cause their levers F to force the rod 1 downward by means of the links H, thereby" causing the front ends of the lever K to be de pressed, the rear weighted end thereof to be elevated, and causing the rod M, connected to its front end, to lower the box S on the rocking arm N, and thereby bring the said box nearer to the center of the rock-shaft H. This necessarily diminishes the stroke of the cutoff valve and causes the latter to admit a diminished supply of steam to the ends of the cylinder at each stroke of the piston, and thereby decrease the speed of the engine. If the engine is running too slow, the balls G will be lowered by gravity and will cause the rod 1 to move upward, and thereby elevate the front end of the lever K, the rod M, and the box S, so as to increase the distance between the said box and the center of the rockshaft H, and thereby increase the length of stroke of the balance cut-oft valve, and consequently cause the latter to admit increased quantities of steam to the cylinder. The rollers U and X serve to lessen the friction be tween the box S and the arm N, and the. slotted plate V,which carries the roller X, is longitudinally adjustable, so that thesaid roller X may be moved nearer the arm Nfrom time to time to take up wear.

Having thus described my invention, I claim l. The combination, in a steam-engine, of the valve stem or rod, the rocking arm N, the rod Z, attached to the valve-stem, a connection between said rod Z and rocking arm N, whereby the former is vertically adjustable on the latter, the weighted lever K, having rod M, connecting it to rod Z, and the governor and rod 1 1, connecting said governor to the weighted 1 lever, substantially as described.

2. The combination, in a steamengine, of the rocking shaft having the arm N, the box S, connected to the said :arm and adjustable vertically thereon, the cut-off valve having the stem or rod, the rod Z, connecting the latter to the box S, the weighted lever K, the governor connected thereto, and the rod M, connecting the lever K to the rod Z, substantially as described.

3. The combination, in a steamengine, of the rock-shaft having the rocking arm N, pro vided with the ears 0, the vertically-movable yoke P, secured to and guided by the said ears, the box S, attached to the said yoke and having the rollers engaging the arm N, one of said rollers being adjustable to compensate for wear, substantially as set forth, the cut-off valve having the stem or rod, the rod Z, connecting the latter to the box S, the governor, the weighted lever K, connections between the governor and the said lever K, and the rod M, connecting the saidlever K to the rod Z, substantially as described.

In testimony that I claim the foregoing as my own I have hereto affixed my signature in presence of two witnesses.

JOHN S. MARSHALL.

NVitnesses:

JOHN H. Sleenns, E. G. SIGGERs. 

